EPI & PPI are the very common word in the textile industry. In woven fabric EPI and PPI is measured to the number of yarn on a fabric. Normally, EPI is the number of wrap threads per inch of fabric & PPI is the number of weft threads of per inch of fabric. After read this article we can easily understand EPI & PPI in textile apparel.
EPI: EPI means “Ends Per Inch” is the popular word in the garments & textile industry. Number of yarn in warp direction is measured by EPI. Normally, ends per Inch are the number of wrap threads. It is the represent vertical thread of the fabric. It is called the wrap yarn.
PPI: PPI means “Picks Per Inch” is also the most popular word in the textile & garments industry. Number of Weft yarn in fabric is measured by PPI. Picks per inch is the number of weft threads of the fabric. It is represent the horizontal threads. It is the called weft yarn.
There are two methods to find out EPI & PPI.
- Testing method in Lab.
- Without testing method or manual.
1.Testing method in Lab
If you want to know EPI & PPI in the fabric then send fabric sample to the testing lab. After checking the fabric sample they will inform you how many Ends Per Inch & Picks per inch on the fabric.
2.Without Testing Lab Or Manual. 
Normally, it he the simple method to way finds out the EPI & PPI on the fabric. Moreover, maximum fabric EPI yarn is the higher than PPI yarn. If you want to know EPI & PPI then you should follow in the below procedure.
- Collect the fabric swatch. Put the fabric swatch on the plain table. And also marks wrap & weft direction of the fabric.
- Mark 1X1 inch on the fabric sample.
- Vertical or wrap yarn count one by one. And find out how many wrap yarns. And also horizontal or weft yarn count one by one. Find out how many weft yarns.
So, using this method we can easily understand & find out one inch fabric yarns count of length & Width.
In the above picture we can see Ends Per inch 9 yarns & Picks per inch 8 yarns respectively.
Md.Mahbub-Ul Islam
RMG Consultant & Researcher.
mahbub@textilemerchandise.com
Very Interesting article.Thanks.